<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <!-- HTML：定义网页的结构和内容 -->
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Web标准示例</title>
    <!-- CSS：定义网页的样式和外观 -->
    <style>
        body {
            font-family: '微软雅黑', Arial, sans-serif;
            background-color: #f0f0f0;
            margin: 0;
            padding: 20px;
        }
        h1 {
            color: #333;
            text-align: center;
        }
        .box {
            background-color: white;
            padding: 20px;
            margin: 20px auto;
            width: 80%;
            border-radius: 10px;
            box-shadow: 0 0 10px rgba(0,0,0,0.1);
            transition: transform 0.3s ease;
        }
        .box:hover {
            transform: translateY(-5px);
        }
        button {
            background-color: #4CAF50;
            color: white;
            border: none;
            padding: 10px 20px;
            cursor: pointer;
            border-radius: 5px;
        }
        button:hover {
            background-color: #45a049;
        }
    </style>
</head>
<body>
    <h1>欢迎来到Web开发概述（HTML）课程的课堂！</h1>
    <div class="box">
        <p>这个页面展示了Web三大核心技术的结合使用。</p>
        <button id="clickBtn">Click Me！</button>
    </div>
    
    <!-- JavaScript：定义网页的行为和交互 -->
    <script>
        document.addEventListener('DOMContentLoaded', function() {
            const button = document.getElementById('clickBtn');
            let clickCount = 0;
            
            button.addEventListener('click', function() {
                clickCount++;
                if (clickCount === 1) {
                    alert('Hello, Web! 欢迎开始你的Web开发之旅！');
                } else if (clickCount === 2) {
                    alert('HTML是网页的骨架，CSS是网页的皮肤，JavaScript是网页的灵魂！');
                } else if (clickCount === 3) {
                    alert('继续探索，你会发现Web开发的更多乐趣！');
                } else {
                    alert('你已经点击了' + clickCount + '次按钮！看来你对Web开发很感兴趣呢！');
                }
            });
        });
    </script>
</body>
</html>